A 60-year-old female was admitted to hospital with a continuous fever, a decreased appetite, and abdominal pain. Laboratory tests showed an elevated peripheral leukocyte count (13,800/μl) and increased C-reactive protein (19.1 mg/dl) and carbohydrate antigen 19-9 (4057 U/ml) levels. Abdominal contrast-enhanced computed tomography showed multiple bulky hypovascular nodules in the liver, swelling of the paraaortic lymph nodes, and a hypovascular mass (diameter 3.0 cm) in the pancreatic body. The serum concentrations of granulocyte colony-stimulating factor (G-CSF) and interleukin-6 were 172 pg/μl and 541 pg/µl, respectively. Liver biopsy specimens revealed an adenosquamous carcinoma, which was positively immunostained for G-CSF. We diagnosed the patient with G-CSF-producing pancreatic cancer with multiple metastases. Four courses of gemcitabine with dexamethasone and one course of nab-paclitaxel and gemcitabine were administered. Although the pancreatic tumor and paraaortic lymph node metastases decreased in size, the liver metastases continued to grow. The patient died 4 months after the diagnosis of pancreatic cancer. An autopsy resulted in the tumor being diagnosed as poorly differentiated adenosquamous pancreatic carcinoma, which was histopathologically G-CSF-positive. Although G-CSF-producing pancreatic adenosquamous carcinomas are extremely rare, they have been encountered more frequently in recent years. In such cases, chemotherapy combined with dexamethasone might be effective at temporarily improving the patient's condition.